Leaky rear main so I might as well do a tranny swap. Which Tranny?

[68EFIvert]

My engine has outgrown my T5 tranny and I am looking at replacing it before it is worthless. I have fixed most of the problems on my car but it looks like I may have a rear main seal that isn't sealing properly. I have a little oil leak coming from the bottom of the bellhousing. Since I have to pull the tranny to change the seal I thought I might as well do the transmission a couple months earlier so I don't have to pull everything out again.

As I mentioned I have a T5 with a JMC hydraulic cluth kit. I have narrowed my choices down to two. A TKO600 or a GForce T5/Astro T5. My understanding is the TKO will bolt right into my car without modifications to the floor pan.

My dilemma is I already have the hydraulic clutch, bellhousing and crossmember for a GForce tranny so I will have less expense if I go that way. I think I may be able to get a bracket for my JMC kit that will fit a TKO transmission and if so that will greatly reduce the costs.

I have heard that the GForce transmissions are noisier than the TKO600 but do not know for sure. It may not be a big deal since the car is already pretty noisy with the blower on it. I am sorry to post another what tranny to buy and would like to hear some of your feedback before I jump into this project. Thanks for the help. I am really leaning towards the GForce unit at this time.

 

[red65]

I've been pretty happy with my Astro A-5, which replaced a Cobra T-5 that my blown 306 promptly destroyed. It's slightly noisier than the stock T-5, and shifting is slightly notchier, but it's lived up to all the abuse I can dish out without complaint. Moreover, it bolted up just like a T-5, which I consider a huge advantage if you've already got all the hardware.

I used a King Cobra pressure plate and a dual friction Mcleod disc, both of which have performed well - I purchased the whole setup from Tony at Astro. Good guy.

 

[Tony R]

Hey Darreld I might be interested in your T5 if you haven't destroyed it yet. I am still looking for a 5 speed for my 65.

 

[68EFIvert]

I've only got 60 miles on the car and other than the first couple they are pretty easy. It has a new tailshaft bushing, seal and steel retainer. I will also throw in the clutch that has the same mileage. But lets talk later. I may blow it up still.

 

[Tony R]

sounds good. If I put it in my car it will be abused as well. Probly not as bad as you have done though.

 

[oz]

Do you have a 1 piece or 2 piece rear main seal?

I ask because you do not need to remove the transmission to replace a 2 piece rear main seal. I've done it and the job only took an hour or so. Unfortunately for me, the oil leak was actually from the rear of the oil pan. Stupid aftermarket stamped oil pan....

 

[68EFIvert]

I can't remember if it is 2 or 1 piece. The gaskek kit I am using was a rebuild kit form Ford that I purchased from Summit 3 years ago. I think it was a 2 piece gasket but I am not 100% sure. How the heck would you replace the gasket? Wouldn't the flywheel be in the way or do you just remove the pan, loosen main caps and slide the gasket out?

 

[5.0ina66]

How the heck would you replace the gasket? Wouldn't the flywheel be in the way or do you just remove the pan, loosen main caps and slide the gasket out?

You got it. But, if it's a 5.0L, it should be a one piece rear main.

 

[68EFIvert]

If so I guess the tranny is coming out and gives me an excuse to get the GForce or Astro A5 tranny.

 

[D.Hearne]

You got it. But, if it's a 5.0L, it should be a one piece rear main.

Nope, Both the 1 & 2 pc seals were used on 5.0's. The "5.0" name started in the 79 model year. The switch to the 2 pc rear seal was sometime in 1982/83